itsafive

I thought the slo-mo of this was really useful to see just how the rider moves his body. https://amp.twimg.com/v/e9e71a02-9a17-43e4-8e6a-96b4939839ab

This sounds just like my 05 used to be. After going round the houses I ended up testing the compression to find it low. New piston and rings sorted it. Also check thermostat- mine was getting too hot, bad news on a 2T with low compression already!

Thanks for all the help guys. Helmet is Hebo Zone c. 1200g. I think I need to try the bars rolled forward a little but I also think I need to really focus on using my legs more.

I always finish a trial with pain at the bottom of my neck between shoulder blades. I am a novice so I could be tense on the bike. Could it be how I have set the controls up? I'm 6 feet tall and the bike is an 05 GG with standard bars.

Hi Andy - Don't know where about in Lincs you are but I can recommend the Lincoln(venues usually near Gainsborough or north/north-east of city) and Pegasus (near Grantham) as great, friendly clubs. My local club is Pegasus and the white route for beginners is usually spot on in terms of difficulty. I found I learn most by entering a trial rather than practice!

Not actually done the job owning a GG but 'Shoe Goo' is perfect for these kinds of jobs. It's like a silicone sealant but incredibly resiliant to peeling off/moving. I use it in combo with glass fibre matt to repair mudguard cracks before they get too bad. Search for it on flea bay.

I fitted a LiPSE (Light Pull Smooth Engagement) Spring fromJack's cycles in the USA. It was for a Pro and the weight of the spring was tailored to the bike & my weight. Great service - he threw in a gasket and a GG keyring too! Just Google 'lipse spring gas gas'. Although this will not reduce clutch usage it will significantly lighten the clutch action.

Entry list now on ssdt.org website. I'm not on it

Hi there Ian. I am a practice member at ESTC although I don't get there nearly enough to practice as it's quite a way from me and you can't go on your own to practice! I also did as you did - went to one trial, broke the bike and myself and left the bike dormant for too long. My advice is to enter a trial on the easy route and have a go! I find that I don't have a go at stuff when practicing that I will try when in a set out section. It's always amazing what the bike will do if you just try. Send me a message if you want to have a practice buddy sometime!

I always have trouble with the same type of section. Imagine a section where you head up a loose, sandy, slope and have to turn to then ride across the slope. When I do this I usually end up with my front wheel slipping back down the slope taking me outside the next set of flags! Can anyone suggest a technique for address this?

This was covered on the forum before - scroll down a few posts for a photo. Basically it sits beneath the tank held against the top frame rail by a bendy tab! Make sure the wiring is neat to allow it to sit as low as possible otherwise the tank will sit proud. http://www.trialscentral.com/forums/topic/28190-gasgas-txt-250-cdi-wiring-info-parts/

I lived the look of the bike covers Montesa used for the launch of the latest 4rt. Any one know where I might be able to source one!

Me too!

I bought a single Halfords Professional combination spanner for this job. Fits like a dream ad wasn't that dear either!

Your video shows exactly the same issue I had. I also found the bike very hard to start wen hot and had to use choke. See my recent thread on 'Hot Starting Issues'. I ended up replacing the piston and rings as the rings were very worn. My theory is that the extra velocity you get from hacking at the kick start gives just enough compression. Bike now starts first kick from cold with the technique shown in the Jim Snell video. When very hot some throttle I required for a first kick start. The job is very easy and can be achieved without removing the engine.

Quick update with thanks to all who helped, especially Dom! I quoted the squish wrong - it was 1.3mm! Disassembled top end and found evidence of blow by on cylinder liner. Ring end gap massive, especially bottom ring which was visibly worn! Cylinder looks in good nick, as does piston. Spoke to factory Kev at GG UK and piston/bore wear within acceptable limits. Sadly piston rings no longer available so had to have a piston kit. Hopefully we will be sorted by the weekend.

Thanks Dom, Mine has very low compression feel at times. Barrel off and measure rings is next I think. Would I reduce squish with a thinner base gasket or would worn con rod bearings cause this?

Thanks for your help. Great community spirit! I checked the squish which is spot on at 1.5mm. Before I took the barrel off and potentially go even further I pulled the flywheel off and there was a distinctly oily smell with some oily deposits on stator. Also found what looks like emulsified oil in bottom of crank seal. See pics on link below: https://www.icloud.com/photostream/#A4532ODWjtzxv So likely crank seal compromised?

The compression is about 135 psi when cold and 120 when hot. Photo of piston and rings thru exhaust port here... https://www.icloud.com/photostream/#A4532ODWjtzxv

I've had a PM suggesting that the 200cc may not be up to the moor crossings. I weigh around 11st 6lb at the moment, although this may rise the more I train for the SSDT itself.

Considering a new bike and prefer something I can thrash rather than fight. Would a lower capacity bike, like a Beta 2T 200cc cut it for a SSDT first timer?

Not convinced that the bowl is dry tbh. Took ignition side cover off to find a very damp environment! More evidence of electrical issues?

It runs just fine one it is going. Ended up doing the last two laps without stopping the engine to avoid having to re-start it!

My bike is an 05 250 Pro. Bought secondhand it has always been a pig to start, especially when hot. Things are slightly better after the following work... Cleaned carb thoroughly, several times. New plug about four rides ago. All fuel filters cleaned (petcock and carb). Rewired and lengthened CDI earth lead as poor wiring at chassis connection. Renewed air filter rubber connection as misshapen with age. At yesterday's Loughborough trial it behaved as is usual - get it up to operating temp, stop at a section to look it over (or queue) and bike won't start. Have to use choke and a big handful of throttle and loads of kicking. Had someone else try kicking and it was hard for them too. Sometimes when it's hot you can kick it over several times and it feels like there is little/no compression. It happens even if you get the piston up top before giving it a good kick. Took plug out. Pretty black and recess near the electrodes full of carbon! I have had suggestions of sticking float needle leaving bowl empty and possible crank seal leaks. Any thoughts? I take it that crank seal replacement is a case apart job?

There is a 'blind' bearing, of a needle roller type, that supports the back of the shaft. If you look from the gear change side of the bike you'll see a silver circle above where the cases join. This is the back of the bearing. Remove the clutch case (drain oil first) and remove kickstart assembly. Knock the bearing out from behind.